直接电加热技术在停井时管道瞬态传热分析  

Analysis of Transient Heat Transfer of Pipeline during Shut-in Well with Direct Electric Heating

作　　者：黄鑫[1] 段梦兰[1] 安晨[1] 王浩[2] Huang Xin;Duan Menglan;An Chen;Wang Hao(Offshore Engineering Research Institute,China Urduersity of Petroleum ( Beijing;College of Mechanical and Transportation Engineering,China University of Petroleum (Beijing))

机构地区：[1]中国石油大学(北京)海洋工程研究院 [2]中国石油大学(北京)机械与储运工程学院

出　　处：《石油机械》2019年第8期132-139,共8页China Petroleum Machinery

基　　金：国家重点研发计划项目“基于深水功能舱的全智能新一代水下生产系统关键技术研究”(2016YFC0303704)

摘　　要：随着油气开采进入深海模式,深水低温高压环境更容易形成水合物并使蜡结晶。如何更好地保障油气运输安全是油气开采以来不断探索的学科与工程问题。目前,国外正在大量使用直接电加热(DEH)技术来解决管道保温问题。鉴于此,从传热学的角度出发,研究了在电磁、热、流三大物理场共同作用下的DEH技术。通过建立电磁热耦合模型,研究了DEH技术应用于瞬态停井工况下整个管道温度的变化规律,得到了加热电流、加热时间和温度三者之间的相互关系。计算结果表明:DEH的加热效率先慢后快,升温效果显著;加热电流越大,油液升温效果越明显,但加热时间过短,过高的加热电流对加热效果影响不大;对比自然温降曲线,在36 h之后会达到水合物和蜡结晶生成的临界温度,而采用了1 000 A电流的DEH技术后,整条管道始终维持正常工作的温度状态。研究结果为DEH的实际工程设计提供了重要参考依据。As oil and gas exploration enters the deep water,hydrates and wax crystals are more likely to form in low temperature and high pressure deep water environment. How to better guarantee oil and gas transportation safety is a subject and engineering problem that has been continuously explored since oil and gas exploration. At present,direct electric heating( DEH) technology is being used extensively abroad to solve the problem of pipeline thermal insulation. In view of this,from the perspective of heat transfer,the DEH technology under the combined action of electromagnetic,thermal and fluid field was studied. By establishing the electromagnetic-thermal coupling model,the variation of the whole pipeline temperature with the DEH technology under the transient shut-in well condition was studied. The relationship between heating current,heating time and temperature was obtained. The calculation results showed that the heating efficiency of DEH is first slower and then becomes faster. The heating effect is significant. Larger heating current resulted in more significant heating effect. However,excessive heating current would provide little heating effect if the heating time is too short. The curve of the natural temperature drop will reach the formation of hydrate and wax crystals after 36 h,but the temperature of the whole pipe will always maintain the normal working temperature after applying the DEH technology under 1 000 A current.

关 键 词：深水 直接电加热 电磁热效应 沿程温降 瞬态传热 耦合 

分 类 号：TE973[石油与天然气工程—石油机械设备]